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Anterior Open Bites: Part IX

Anterior Open Bites: Part IX

The easiest open bite to correct is one that was caused by tooth wear from erosion, not attrition or grinding, and where the anterior tooth position didn’t change with the tooth wear. These are also very uncommon patients, as normally eruption will occur following the wear maintaining the teeth in occlusal contact.

Open Bite Caused by Lemon Sucking

The patient in this open bite example is a male in his 50s, and he has a 25 year history of sucking lemons (Figure 1). A lateral view shows the posterior teeth from first premolar back are all in contact, although they do show some evidence of facial erosion (Figure 2). He bit through the lemon with his incisors and sucked the juice out around them, in the process he actually devitalized 3 of the 4 incisors (Figure 3). Simply looking at this image doesn’t make it clear whether his anterior teeth have extruded with the tooth wear or not (Figure 4).

It will be necessary to identify the correct incisal edge position of his teeth, then evaluate how the gingival levels relate to that position using width to length ratio as an assessment of whether the gingival margins are correct or not. This will tell you whether the teeth have erupted with the wear or not. In this case the drawings are done to illustrate the correct incisal edge position for this open bite patient, basically level with his posterior occlusal plane. Measuring from the correct incisal edge to the existing gingival margins gives a ratio of 77 percent, a very common ratio for a pleasing central incisor. It appears he has no secondary eruption with the tooth wear, and will simply need the teeth restored without any gingival level alterations (Figure 5).

The good news is that because he had the open bite, there was room to place the restorations. The even better news is that if he keeps sucking on lemons, the acid will have no impact on the porcelain restorations. Of course it would be better for all his other teeth if he quit the habit. Ultimately, due to finances, he only did the maxillary 6 anterior teeth; it would have been ideal if he could have gone back to the first molars (Figure 6).